Have a 1996 Chevy K1500, 5.0L 305 Vortech. Had a P1351 code, found that if I unbolted coil and bracket from engine block and positioned bracket so it did not contact any other metal, truck will fire and run perfect, Ground issue? If so ho do I fix it?
I think something wrong with coil? Just my opinion. The ignition module grounds primary circuit of coil in order to induce spark. The ground is a pulse. A solid ground and there is no spark. That's the way I understand it. The coil shouldn't ground to mounting bracket or metal part of engine. I'm not an electrical engineer. Your post is interesting.
coil and icm are both new, didn't have issue after installing new parts, came on sudden , after about 2 months after replacing coil and icm, sent truck to carx, they couldn't figure it out, kinda came across unbolting coil&icm bracket myself by accident
Maybe the coil has developed a bad spot in the insulation, when it touches metal it is grounded and it shorts out. Try a new coil.
Just to add. p1351